All of a sudden, the fan on the air conditioner got faster?

1995 Hyundai Elantra 1.8 ODC, mileage: 62,000. I was driving and pulled out in traffic, so I had to gun it some. When the engine spead up, all of a sudden the fan on the air conditioner got faster, BOTH headlights blew out, and the air bag light came on. The culprit was the alternator voltage regulator. I had the alternator replaced and replaced the headlights myself. The airbag light is still on. Everything else works fine. HERE IS MY QUESTION. How do I get the airbag light to reset? Is it a switch that you just reset or do you think it fried something in the circuit? If so, what and can I replace it myself? The car repair place wants $45 just to hook it to a computer to see what's wrong. Please help and save me some money if you can.